As one of us (Verbrugge) disclosed in U.S. Pat. No. 4,358,573, polymers comprising (1) maleic anhydride, (2) at least one "lower" 1-alkene (i.e., an alpha-olefin having from about 4 to about 16 carbon atoms in its carbon chain), and (3) at least one "higher" 1-alkene (i.e., an alpha-olefin having about 18 or more carbon atoms in its carbon chain) are known to possess certain "waxy" qualities, which is desirable in certain applications. For example, possessing such "waxy" qualities enables certain polymers to be used as mold-release agents and other so-called "slip" agents, as well as certain additives to floor polish formulations, other surface-formulation compositions, and the like. In particular, polymers of this sort typically function as water-soluble anti-redeposition agents, and accordingly, such polymers can generally be readily formulated into a variety of compositions, one such composition being a liquid-detergent formulation.
Methods for producing polymers comprising maleic anhydride and alpha-olefin monomeric units are generally well known and are disclosed, for example, in U.S. Pat. No. 3,461,108 to Heilman et al.; U.S. Pat. No. 3,488,311 to Burdick et al.; as well as U.S. Pat. Nos. 3,553,177; 3,560,455; 3,560,456; 3,560,457, all to Hazen et al.; and U.S. Pat. No. 4,250,289 to Denzinger et al. While these patents collectively disclose a variety of processes--as well as a variety of systems--to produce a complementary variety of desired polymer products, each disclosed process and system requires utilizing either a highly-specific solvent or a complex, so-called "solvent system" (i.e., generally involving a complex solvent mixture), or both, to produce the disclosed polymer. Moreover, these patents each teach using relatively significant amounts of solvent, which can be economically undesirable because such solvent is typically ultimately separated from the thus-produced polymer. In particular, the solvent separation step, oftentimes performed utilizing conventional or so-called "improved" distillation techniques and equipment, can be costly.
In particular, many solvent-based polymerization-reaction processes and systems, such as those disclosed in the above-identified patents, are oftentimes economically unattractive, and thus are generally not widely practiced commercially. Still more particularly, the "economic unattractiveness" generally comes about not only because the solvent must be separated (i.e. "stripped") from the thus-produced polymer before such polymer can be utilized for its intended purpose, but also because certain, occasionally relatively "specific" pieces of processing equipment--many typically involving capital investment, maintenance, and manpower to operate--are required.
Accordingly, it would be desirable to produce polymers, of the type discussed herein, in a process--as well as in a system--that utilizes a relatively inexpensive, solvent-lean reaction medium, and which involves, as a result, minimal solvent-extraction expense.